Process of making chlorhydrins.



K. P. McELROY.

PROCESS OF MAKING CHLORHYDRINS; APPLicATmN HLED JUNE 17. 1915.

1,%3,61L 6, Patented Jan. 15,1918.

d can an a rnn r on on.

KARL lP. MCELROY, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR, T09@HldlhUlUATa DEVELOPMENT COMPANY, OF WASHINGTUN, DISTRICT OF COLUMBIA, ACDEPUlTtA 'rron or MAINE.

To all whom it may concern:

Be it known that I, KARI. P. McELnor, a citizen of the United States,residing at Washington, in the District of Columbia,

have invented certain new and useful limprovements in Processes ofMakingChlorhydrins, of which the following is a specification.

This invention relates to the process of making chlorhydrins; and itcompriws a method or converting gaseous or volatile olei'ins, ormixtures of olefins such as occur in oil gas,-into chlorhydrins ormixtures of chlorhydrins, wherein such an olefin or gas comprisingolefins is exposed to the action of gaseous chlorin in the presence ofwater vapor or steam; all as more fully hereinafter set forth and asclaimed.

The gaseous and volatile olefins, ethylene, propylene, the butylenes,the ainylenes, etc., are hydrocarbons of the. general formula C H 'andchemically considered are unsaturated bodies, the amount of hydrogen ithas proved difficult to oxidize the olefins directly and limit theoxidation; to produce the desired derivatives without burning thehydrocarbon entirely. The present invention has for one of its purposesthe provision of a simple, ready and economical method of producingmaterials from which these potentially valuable oxidized derivatives canbe made.

The olefins readily enter into reaction or combination with chlorin; thereaction being, undersome circumstances, explosive in its violence. Butwith porper control of temperature and other conditions to prevent thereaction going on destruct velyethylene and all the other olefins oncontact with chlorin are presumed to give as a main product the olefinchlorids, C lLnClgethylene givin ethylene dichlorid or Dutch liquid,

C l-l, .1 These olefin chlorids are valuable bodies for manypurposcsalthough not now technically produced owing to the expense ofthe usual sources of olefins andthe dim- Specification 0t EetteraPatent.

Patented can. at, rate.

Application filed June 117, with. Serial No. aae'za.

eulty of the operation. They are heavy liquids, wholly insoluble inwater and While they may be converted into other derivatives of theolefins by inetathetical reactions, they are so little reactive that theyields are poor andthe operation expensive. For such conversionstherefore the corresponding bromids are usually employed instead of thechloride when other olefin derivatives are desired for laboratorypurposes.

T have however found the reaction-0t chlorm upon the olefins, instead ofproducing olefin chlorids, under proper conditions can -be directed inquite another direction with the unexpected result of producing bodiesof quite another class, the chlorhydrins. olefin chlorhydrins ditlerfrom the olefin chlorids in that they have only one atom of chlorin inlieu of two and in that they also carry oxygen" and hydrogen in the formof The what is known as alcoholic h droxyl. Their Y general formula is Cll-1 ,0 Cl. Ethylene chlorhydrin, for example, is CH,C.CH,;OH. It willbe perceived that it diders from ethyl alcohol, CH .CH OH, in that ithas one atom of hydrogen replaced by chlorin. This clilorhydrin beingatonce an alcohol and a chlorin compound has a wide range of solventpower, aiid although at present unknown in the arts has, because of itssolvent power, a great otentialvalue.

Unlike the o efiii chlorids, the chlorh drins are readily reactivebodies and may e easily and cheaply converted into glycols, acetates,beiizoates, nitrates, oxids, etc. They are an excellent raw material forthe other hitherto commercially unknown oxidized proximate derivativesof the olefiiis.

In the production of olefin chlorids the net result of the action isthat. the olefin molecule takes 11 Cl and forms the chlorid, e tr ce.lit ch orin in excess be resent it is apt to form higher chlorinatedodies by what is called substitution; the entrance oi an atom of chlorininto the molecule replacing an atom of hydrogen.

l have found that it the contact of chlorin lllltl water increases thecharacter of the reaction changes and the chlorhydrin-producing reactiontakes place. In producing this latter reactionin the presence ofliquidwater the chlorin possibly hydrolyzesto'form hydrochloric acid andhypochlorous acid (HOCl) ,and the latter then unites with the olefin. 16But thechlorhydrin-forming action however goes forward after suflicienthydrochloric acid has developed to preclude the.

existence of hypochlorous acid, even tern orarily. In another.application, Ser. 0.

w asses, filed June 22,1915,7I have described and claimed broadly theapplication of this fact to the production of chlorhydrins, chlorinbeing formed in or supplied to an aqueous bath which-is kept saturatedwith the olefins so that the latter may bein excess in the sphereofreaction. In the present invention I produce the chlorhydrins infthepresence 0 steam.

. so .1 have found thatif I'dilute dga'seous olefin and chlorin withwater vapor m sufiicient amount instead of the chlorin combiningdirectly with the olefin, as in making the olefin chlorids, there is ,a'reaction, which me. be termolecular, with the production of hy ochloricacid and chlorhydrin. The total reaction may lows:-.

1.+C. c1+c.a..or1c1. Hydrochloric acid forms a valuable by-product. Thereaction isbest carried out at about 100 C. and the dilution ofthe gasesy with the water vapor should be rather high. a At' 100"; C. underatmospheric pressure, steam and water can coexist and the presence ofboth is useful; the steam to maintain the-dilution and the water to'absorb and re move the 1101 as it forms. At about 100? 0.,thecondensation of -'water as a l fog scrubs the HCl out of the va ormixture without-taking "down chlorhy rins. It is best to add the chlorinportionwise "and maintain some excess of the olefin even at the end. Thereasonfor these precautions. is thatthe direct union of olefin andchlorin to. form the olefin chlorid is a rather rapid reaction while theformation of chlorhydrin,

' which involves reaction of three molecules,

his somewhat slower, although I find that under proper conditions it ispreferential.

. The chlorhydrin forming reaction under the present invention is onedependin in lca'fige measure upon relative concentrations. orin shouldalways be in relatively low 'ency to convert chlorhydrins' 'into "olefinother by distillation is not 'ready, although,

water in the vapor state or as' be se arate into chlorhydrins.

be formulated" as folo may be converted into ethylenechlorhydrin,

' the olefinic gases.

concentmtion, both to avoid formation of olefin chlorid and. to preventundesiredchlorination or oxidation of the chlorhydrin produced. 1 The"concentration of the olefin 18.11. excess, however slight. Theconcentration or steam or water .in thereaction zone,

or in other words, the amount relative to the .olefiri and-chlorin inadmixture therewith should be rather lar e. ,The reaction ,5

is one developing much eatland this is taken up by the steam. Inoperating, at the temperature of-condensing" steam, the-'presence ,ofmuchwater vapor and the presence of liquid water, keep the hydrochloricacid at a ow concentratlon in the gaseous reaction mixture; .which isuseful, hydrochloric acid in highconcentration having a tendchlorids. Iv u All the chlorhydrins of the lower or gaseous olefins boil at aboutthe same temperature and their separation from each.

it may be effected by taking advantage of the fact that those withmorecarbon distil first in the resence of steam. Or they ma 5 byconversion into oxids whic readily fractianated and reconverted Wherepure chlorhy-.. drins are desired, it is therefore better to usesubstantially pure olefins. I regard my inmay vention as' a plicable tothe treatment of any of the o efins which are normally gaseous or can beconverted into vapor in the presencebf steam. Ethylene, for example,

propylene into pro ylene chlorhydrin, and so on..- Ethylene intended forconversion into chlorh drin may be made in any mannor desire as bydehydrating alcohol,

at a low temperature. Ordinary coal is is usually fixed-- and containsvery litt e of In' the -'accom an'ying drawing I have I shown more'oress dlagrammatlcally certam organizatlons of apparatus elements usefulin performing the described process.

In this showing:

Fi e l isa view partly in central longitu 'fal section and partly inelevation of one form ofapparatusgand 1 Fig. 2 is a similar view ofanother form.

aaaaeae In Fig. 1 element 1 is a casing which may be made of stoneware,stone slabs or other material ada ted to resist the action of chlorin orby rochloric acid. In its base it v is provided with steam coils 2 forheating purposes. It is divided by alternatin depending baiiies 3 andintermediate baihes 4 so as to ive a circuitous pathway for mixed usesan steam. As shown the 'intermediate aiiles dip into the surface of abody of boiling water or weak hydrochloric acid 5 in the base of thecasing. Steam main 6 furnishes steam. Gas enters at one end of thechamber through 7, being sent into the chamber and admixed with steam byinjector 8. Chlorin may be sent into the chamber at a variety of pointsfrom chlorin main 9 by means of valved feed pipes 10, 10", etc., eachprovided with'a steam injector 11. At the other end of the casing isdraw ofi 12 for hydrochloric acid. At the top of the casin is vaporoutlet 13 leading to element 14 w ich in substance is a column still andliquid to be sent elsewhere.

The apparatus of ,Fig. is the same in principle but instead of usmoutside steam for dilutlon'of gas and chlorin the vapor in the apparatusis relied upon. In this showing 23 is an acid proof casing provided withgage glass 24, draw 0d 25 for acid and pressure gage 26. At its base itis adapted to hold a body ofliquid '27. Dipping into the liquid ischlorin pipe 28 having a minutel perforated cross-pipe 29: Endingimmediately above the liquid is 1gas pi e 30. Steam pipes 31 provideheat. rom t 1e top of the casing leads fractionating column 32 providedwith waterinlet 33. Vapors are led by pipe 34 to worm 35 in tub 36.Condensate passes to collecting tank 37 whence gas escapes at 38 andliquid is drawn od at 39.

In the employment of the structure shownin Fig. 1, gas which may be apure olefin or may be a mixture containing a number of olefins, such asoil gas, is taken in from supply main 7 by the action of steam in-.jector 8, which dilutes it uniformly with steam. Chlorin is similarlyintroduced from 10= by steam jet 11. The mixture of steam, chlorinandgas is forced to take a tortuous passage through the casing by thealternatmg babies or partitions during which com-" -pass on to condenser15 bination with formation of chlorhydrin takes place. The provision ofa number 01" chlorin inlets '10", 10, etc., renders it p 1;

sible to introduce the chlorin in successive small fractions; and thisis in general the best way of operating. During the operation the liquid5 is kept at the boiling point by coils 2, furnishing most of thediluent water vapor necessary in operating the chamber. It is usuallbest to introduce only a small amount 0 steamby the steam jets; anamount corresponding to the amount of water taken away as dilutehydrochloric acid and as chlorhydrin solution. Hydrochloric. acid isremoved. at outlet 12 from time to time or continuously. When thechamber is run properly the body of liquid will contain substantially nochlorhydrin; and if the gas be clean, it will contain very litte organicmatter. The acid may be concentrated and recovered for commercialpurposes in any of the known ways. While it may be delivered from 12 ata stronger cc'icentration, say '19 to 20 per cent, I prefer to deliverit at about ,10' per cent. strength.

,With the liquid in layer 5 of only 10 per cent. strength, little HCIgas will remain in the chamber gases. The resence of much HCI '13. Theboiling point of the chlorhydrins produced from oil gas when-in a drycondition is between 125 and 135 0.; but in the presence of water vaporthey are freely volatile at 100 and -below. The effluent gases passingthrough 13- enter column still 1-1. where most of the acid and water arecondensed and returned to the chamber. The gas, the chlorhydrin and somewater vapor and thence into tank 17.

Using oil gas and obtaining the corresponding mixture of chlorhydrins,if 11 be an efficient typeof still-and the operation be relatively slow,the condensate delivered by 15 will be a milky mixture of heavy oilydrops ofchlorhydrins with a saturated solution of chlorhydrins. Thismixture maytion of chlorhydrin as a condensate in this condensate beingthereafter neutralized or redistilleol. But it regard it as. moreadvantageous to prepare a distillate so strong that chlorhydrins willseparate, not only "slows the reaction an may convert some ct because iiobtain my product directly and simply but because the stronger thedistillate the less acid will accompany it.

50 33 performing a useful function in diminishor after redistillation,may be treated with a little chalk or sodium carbonate to neu; tralizefree acid and then'dried by distiJla.--

tion or by chloridof calcium. The mixture of chlorhydrins obtainedi'ir'om oil'gas'is a clear, heavy liquid, Sinkingin-w'ateraa-nd aleasant odor, 'is' an excellent solvent of ce ulose acetate and manyother "goatingmaterials and boils and otherwisebehaves,

like a unitary body.

. The reaction 'chambersliould beef ample size to afford time-for 'thechlorhyd'rin ,re-'

actionto occur in the passage'of gas therethrough and to allow ampledilution of gas and chlorin with steam. .The mixture of the threereactinglbodies, gas, steam and chlorin, should be as intimateas-possible.

The rovision of a number of inlets for the chlorm while notindispensable isnevertheusing oil gas or pure olefins, shall show a'flittle'remaining olefin, but no substantial amount, say not over 5 percent. on treat-.

ingwith-bromin in the ordinary gas analysis apparatus; and so that nooils insoluble in water appear at the condenser. As stated,-

chlorhydrins may, and usually do separate from the condensate; buttheyare soluble in water, usually dissolving in about twice their volume ofwater. The olefin chlorids, on the other hand, are insoluble in waterand if the distillate shows an oily separation which willnot whollyredissolve on dilution, olefin chlorids are being formed because of alocal concentration of chlorin somewhere in the chamber. In this event,manipulation of the several chlorin inlets will obviate the difliculty.

The operation of Fig. 2 is substantially the same save that the boilingof the liquid is relied on to furnish water vapor. The

chlorin in bubbling through the liquid isthoroughly diluted with vapor.No steam being furnished the chamber, water is led in at ing the amountof acid passing thereabovje. The temperature of the reaction chamber maybe at any point desired, but 100? (L. or

a temperature corresponding to the boiling point at atmospheric pressureworks well and is convenient. By 'ralsing or lowering In the present;operation it "is desirable to have both liquid and vapor present and to--have a body of boiling liquid which furnishes most of the water vapornecessary for ca ing point of course dep m9p lf diluent and reactionpurposes; but the boil- 'wit . 1" Where-olefin chlor de areproducedinany quantity they can do separatdby distillatron m the samemanneras'jand with the olefin chlorids and. afterward separated bywashing with water. The' chlorhydrins being soluble dissolveto formasolution-from I j which they may" beafterward recovered by distillation.stated, the olefin chloride are also valuable bodies. However thepresent-iinvention being rimarily intended for the roduction of c loihydrins it is ordinar' y'desired to adjust conditions within thechamber so as to produce-a distillate 4 which is completely soluble inwater.

Any oil as-may-be used in the present invention w ich-has not been fixedor 0th erwise treated by exposure to a high temperature; but it is bestto use one made at a moderately low temperature, say around 700 (3., bypassing crude petroleum, gas oil,

. heavy residues,'etc., through ahot tube or retort.- Highly naphthenicoils are not as good as parafiin base oils. Working der ordinaryconditlons of pressure with an' iron retort, such gas will run about 45to 50 er cent.' totalolefin, ethylene, propylene,

utylenes and amylenes; 35 per cent. or morebeing ethylene and propylenetogether. The

relative proportions o gases will however vary considerabl with themethod of manufacture and puri cation adopted. Gasification underreduced pressure gives a better and richer gas. An expedient which leadsto economy in oil is to return'to the gasifying zone a: portion of thewaste gas after the olefins have been absorbcd therefrom, gasifying theoil in its presence. With return of some gas and the use of reducedpressures in gasifying important economies inoil may be secured.

Instead of making oil gas by gasi i-ng oil. in a retort, thegases'formed'in sti ls used for distilling petroleum may be employed.The gas'given' oil in the first stages of distillation is not ordinarilyrich in olefins but that from the later stages, and especially incracking, is often quite rich. Instead of oilgas, a gas made by cokingcoal or charring wood at low temperatures under reduced pressures may beemployed; but oil gas I consider the best. material. I

Theoil gas may be submitted to the usual cooling, scrubbing and urifyingto remove unchanged oil, tar, sul r, etc. making theparticularchlorhydrin mixture of the ally contains some acetylene, orbodies of the the various olefinic.

present invention, readily condensableolefinsshpuld also be removed. Thegas usuacetylene series, which can be removed. This.

may be done by passin he gas over metallic cop magma containing copperhydrate, etc. A magma formed by precipitatin co er sulfate. solutionwithhmexwor e ciently.

or at 25Q to 300' or by scrubbin it a solution of copper acetate, wit arename Whether the gas be further treated depends upon the character ofthe gas and the nature of the chlorhydrins desired. If a mixture ofethylene and vpropylene chlorhydrins be desired, while other methods ofpurificatlon be desired, the gas is best next compressed to 75 or 100pounds and cooled. Thls removes by condensation .the bulk of thebutylenes and amylenes; which may be sources and in a pure 'stateemay beused in I the present process; ethylene, for example being readilyproducible by hydrogenating acetylene in the presence ofcatalysts. Pureol'efins produce pure chlorhydrins. But as stated, the mixture ofchlorhydrins made from the. mixed olefins of oil gas is, for

the present purposes more desirable than the pure individualchlorhydrins.

Where pure chlorhydrins are required for any purpose it is moreeconomical to produce the mixture of the present invention, break upwith caustic soda to make olefin oxids, fractionate these oxids and'thenre convert to chlorhydrins with-hydrochloric acid.

' space and introducing chlorin and an olefin- In working with anuncompressed gas or gas not scrubbed with oil to take out higherolefins, where a-pure hydrochloric acid as a by-product a desideratum,the gas may be scrubbed with hot hydrochloric acid which, of course,takes out all components soluble in or combining with hydrochloric acid.With a gasrich in amylenes, this acid scrub oders the further advantagethat some of theamylenes are removed as monochlor pentanes whic may berecovered and converted-into amyl alcohols (tusel oil) or theiracetates.- The condensate'from compressed and chilled gas .is rich inamylenes and may be directly used for making chlorpentane withI HCi.

What I claim is:

i. The process of making chlorhydr ns which comprises establishing andmaintaining a body of boiling aqueous liquid in a suitable reactionchamber having a vapor into such chamber so asto mix in such vapor.space. I

2. The process of making chlorhydrins which comprises establishing andmaintaining a body (if-boiling aqueous liquid in a suitable reactionchamber having a vapor space and introducing chlorin and oil gas intosuch chamber so as to mix in such vapor space.

3. The process of making chlorhydrins which comprises admixing gaseouschlorin. an olefin and water vapor in a suitable vapor space in thepresence of a bath of an aqueous liquid at about the boiling point,cooling the vapors resulting to a sufiicient degree-to condense out mostof the water and of the hydrochloric acid resulting from the reaction,returning the condensate to the bath and further cooling the vapors toproduce condensed chlorhvdrin and water.

4. The process of making chlorhydrin which comprises admixing gaseouschlorin, oil gas and water vapor in a suitable vapor space in thepresence of a bath' of an aqueous liquid'at about the boiling point,cooling the vapors resultingto a sufficient deof the hydrochloric acidresulting from the reaction, returning the condensate to the bath andfurther cooling the vapors to produce condensed chlorhvdrin and water.

5. The process of making chlordydrins and hydrochloric acid whichcomprises establishing and maintaining a body of aqueous liquid at aboutthe boiling point in a suitable reaction chamber havmg a vapor space.and supplying steam, gaseous chlorin and gaseous olefin so as to mix insuch va or space to such chamber while withdrawing concentratedchlorhydrin vapors and hydrochloricacid solution therefrom.

6. The process of making chlorhydrins and hydrochloric acid whichcomprises establishing and maintainin a body of aqueous liquid at aboutthe boi ing point in a suitable reaction chamber havmg a vapor space,and supplying steam, gaseous chlorin and gaseous olefin so as tornix insuch vapor space to such chamber while withdrawing concentratedchlordydrin vapors'and hydrochloric acid solution therefrom, the supplyof steam, gas and chlorin and the withdrawal or" solution being at sucha ratio as to maintain a relatively low concentration ofhydrochloricacid in said aqueous body.

7. The process of making chlorhydrins' which comprises allowing gaseouschlorin to react upon a gaseous olefin in the presence otsutiicientwater vapor to restrain the 'gree to condense out most of the water and9. The process of making chlorhydrins -which comprises producing amixture cit chlorin, a gaseous olefin and water vapor the presence atliquid water the amount at additions.

such water vapor bein suflicient to restrain the formation of olechlorids. to asubstantial extent. L v

10. The process of making chlorhydrins which comprises producing amixture of chlorin, oil gas and water vapor in the presence of 'quidwater, the amount of such water vaporbeing-suificient to restrainsubstantially the formation of olefin chlorids.

'11. The process of making chlordydrins which comprises producing amixture of an olefin and water vapor and adding chlorin to such mixturein a plurality of successive 12. The process of making chlorhydrinswhich comprises producing a mixture of steam and oil gas and addingchlorin to such mixture in a plurality of successive additions. I I

13. The process of making chlorhydrins which comprises transmitting amixture of steam, oil gas and chlorin through a chamber heated to a;temperature around 100 removing the gases and vapors from the chamberand coolin to *condense and recover the produced c lorhydrins. a

14. The process of making chlorhydrins which comprises transmitting amixture of steam, oil gas and chlorin through a chamber heated to atemperature around 100 in the presence of material adapted to absorbHCl, removing the gases and vapors from the chamber and cooling to,condense and recover the produced chlorhydrins.

15. The process of making chlorhydrins which com rises transmitting amixture of oil gas an steam through a chamber at a temperature around100, adding chlorin to the mixture at a plurality of pointsin itscourse, removing the ases and vii 01's from the chamber and coo in tocon ense and 'recover the produced ch orhydrins.

16. The process of making 'chlorhydrins which comprisesblowing steam andoil gas into and through a horizontal bafiled chamber ina circuitouspath, said chamber being maintained at a temperature of about 100 C. andcontaining a bod of hot water to act'as an absorbent for C1 and tofurnish vapor reinforcing the amount of steam, removing the hot vaporsand gases and condensing to obtain chlorhydrins.

In testimony whereof, I "aflix my signature.;

K. P. McELROY.

